Long horizons reward people who can remain emotionally stable through ordinary fluctuations.

Everything long-term fluctuates, and most of the fluctuation means nothing. People who do well over long periods are not immune to it. They just do not treat every dip as a signal, which means they are not constantly making large decisions in response to ordinary noise.

Decide in advance what would actually count as a signal worth acting on. Everything below that threshold gets noticed and not acted on. Most of what happens will fall below it.